From 71ac33596836519a341001bb48a8835b8af75cd3 Mon Sep 17 00:00:00 2001 From: Lorenz Meier Date: Wed, 16 Oct 2013 21:43:11 +0200 Subject: [PATCH] Small improvements to autoland, ensure that throttle can be shut down close to touch down. Depends on accurate land WP altitude --- src/lib/external_lgpl/tecs/tecs.h | 5 +++ .../fw_pos_control_l1_main.cpp | 32 +++++++++++++++---- .../fw_pos_control_l1_params.c | 1 + 3 files changed, 31 insertions(+), 7 deletions(-) diff --git a/src/lib/external_lgpl/tecs/tecs.h b/src/lib/external_lgpl/tecs/tecs.h index 2ae6b28bb4..4a98c8e974 100644 --- a/src/lib/external_lgpl/tecs/tecs.h +++ b/src/lib/external_lgpl/tecs/tecs.h @@ -94,6 +94,11 @@ public: // Rate of change of velocity along X body axis in m/s^2 float get_VXdot(void) { return _vel_dot; } + + float get_speed_weight() { + return _spdWeight; + } + // log data on internal state of the controller. Called at 10Hz // void log_data(DataFlash_Class &dataflash, uint8_t msgid); diff --git a/src/modules/fw_pos_control_l1/fw_pos_control_l1_main.cpp b/src/modules/fw_pos_control_l1/fw_pos_control_l1_main.cpp index cd4a0d58ef..3697af225e 100644 --- a/src/modules/fw_pos_control_l1/fw_pos_control_l1_main.cpp +++ b/src/modules/fw_pos_control_l1/fw_pos_control_l1_main.cpp @@ -196,6 +196,8 @@ private: float throttle_max; float throttle_cruise; + float throttle_land_max; + float loiter_hold_radius; } _parameters; /**< local copies of interesting parameters */ @@ -227,6 +229,8 @@ private: param_t throttle_max; param_t throttle_cruise; + param_t throttle_land_max; + param_t loiter_hold_radius; } _parameter_handles; /**< handles for interesting parameters */ @@ -342,6 +346,7 @@ FixedwingPositionControl::FixedwingPositionControl() : _parameter_handles.throttle_min = param_find("FW_THR_MIN"); _parameter_handles.throttle_max = param_find("FW_THR_MAX"); _parameter_handles.throttle_cruise = param_find("FW_THR_CRUISE"); + _parameter_handles.throttle_land_max = param_find("FW_THR_LND_MAX"); _parameter_handles.time_const = param_find("FW_T_TIME_CONST"); _parameter_handles.min_sink_rate = param_find("FW_T_SINK_MIN"); @@ -404,6 +409,8 @@ FixedwingPositionControl::parameters_update() param_get(_parameter_handles.throttle_max, &(_parameters.throttle_max)); param_get(_parameter_handles.throttle_cruise, &(_parameters.throttle_cruise)); + param_get(_parameter_handles.throttle_land_max, &(_parameters.throttle_land_max)); + param_get(_parameter_handles.time_const, &(_parameters.time_const)); param_get(_parameter_handles.min_sink_rate, &(_parameters.min_sink_rate)); param_get(_parameter_handles.max_sink_rate, &(_parameters.max_sink_rate)); @@ -625,6 +632,9 @@ FixedwingPositionControl::control_position(const math::Vector2f ¤t_positio _tecs.update_50hz(baro_altitude, _airspeed.indicated_airspeed_m_s, _R_nb, accel_body, accel_earth); float altitude_error = _global_triplet.current.altitude - _global_pos.alt; + /* no throttle limit as default */ + float throttle_max = 1.0f; + /* AUTONOMOUS FLIGHT */ // XXX this should only execute if auto AND safety off (actuators active), @@ -634,11 +644,12 @@ FixedwingPositionControl::control_position(const math::Vector2f ¤t_positio /* get circle mode */ bool was_circle_mode = _l1_control.circle_mode(); + /* restore speed weight, in case changed intermittently (e.g. in landing handling) */ + _tecs.set_speed_weight(_parameters.speed_weight); + /* execute navigation once we have a setpoint */ if (_setpoint_valid) { - float altitude_error = _global_triplet.current.altitude - _global_pos.alt; - /* current waypoint (the one currently heading for) */ math::Vector2f next_wp(global_triplet.current.lat / 1e7f, global_triplet.current.lon / 1e7f); @@ -712,16 +723,23 @@ FixedwingPositionControl::control_position(const math::Vector2f ¤t_positio /* apply minimum pitch (flare) and limit roll if close to touch down, altitude error is negative (going down) */ // XXX this could make a great param - if (altitude_error > -20.0f) { - float flare_angle_rad = math::radians(15.0f);//math::radians(global_triplet.current.param1) + if (altitude_error > -10.0f) { + + float flare_angle_rad = math::radians(10.0f);//math::radians(global_triplet.current.param1) + + /* set the speed weight to 0.0 to push the system to control altitude with pitch */ + _tecs.set_speed_weight(0.0f); _tecs.update_pitch_throttle(_R_nb, _att.pitch, _global_pos.alt, _global_triplet.current.altitude, calculate_target_airspeed(_parameters.airspeed_min), _airspeed.indicated_airspeed_m_s, eas2tas, - true, flare_angle_rad, + false, flare_angle_rad, _parameters.throttle_min, _parameters.throttle_max, _parameters.throttle_cruise, math::radians(_parameters.pitch_limit_min), math::radians(_parameters.pitch_limit_max)); + /* kill the throttle if param requests it */ + throttle_max = math::min(throttle_max, _parameters.throttle_land_max); + /* limit roll motion to prevent wings from touching the ground first */ _att_sp.roll_body = math::constrain(_att_sp.roll_body, math::radians(-20.0f), math::radians(20.0f)); @@ -785,7 +803,7 @@ FixedwingPositionControl::control_position(const math::Vector2f ¤t_positio _loiter_hold = true; } - float altitude_error = _loiter_hold_alt - _global_pos.alt; + altitude_error = _loiter_hold_alt - _global_pos.alt; math::Vector2f loiter_hold_pos(_loiter_hold_lat, _loiter_hold_lon); @@ -862,7 +880,7 @@ FixedwingPositionControl::control_position(const math::Vector2f ¤t_positio } _att_sp.pitch_body = _tecs.get_pitch_demand(); - _att_sp.thrust = _tecs.get_throttle_demand(); + _att_sp.thrust = math::min(_tecs.get_throttle_demand(), throttle_max); return setpoint; } diff --git a/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c b/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c index d210ec7126..9b64cb047a 100644 --- a/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c +++ b/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c @@ -72,6 +72,7 @@ PARAM_DEFINE_FLOAT(FW_THR_MIN, 0.0f); PARAM_DEFINE_FLOAT(FW_THR_MAX, 1.0f); +PARAM_DEFINE_FLOAT(FW_THR_LND_MAX, 0.0f); PARAM_DEFINE_FLOAT(FW_T_CLMB_MAX, 5.0f);